Abstract

Chlorination remains a predominant method for disinfecting drinking water. Electrogeneration of chlorine has the potential to become the favoured method of chlorine production if costs can be lowered and chlorine generation efficiencies can be improved. A novel perforated electrode flow through (PEFT) cell design has been developed to address these problems. The electrodes were made from low-cost graphite sheets and stainless steel mesh and separated by a non-conducting fabric membrane. This electrode configuration allows reduction of electrode separation to 0.1 mm or less, minimizing cell resistance and increasing electrical efficiency. The new PEFT configuration generates hypochlorite from a 0.5 mol L⁻¹ brine at a current efficiency of better than 60%. As an inline in situ device, it produces chlorine concentrations known to be sufficient to disinfect water, from chloride concentrations as low as 0.004 mol L⁻¹ (available in most natural waters) by a single pass of the water through the cell operating at 11 V. The possibility of a portable device operated by a 12-V battery is indicated.